All content was written and produced by the National Center for Science Literacy, Education, and Technology, at the American Museum of Natural History. Ellen V. Futter, President.

This publication was developed with support from the Carnegie Corporation of New York.

Credits
Designed by Design Five, Inc., NYC
Written by Jordan Brown

FOR THE AMERICAN MUSEUM OF NATURAL HISTORY:
Allison Alltucker, Producer
Tom Baione, Production Coordinator
Ro Kinzler, Ph.D., Earth Scientist
Patty Abt, Art Director

WEB ADAPTATION:
Patty Abt, Art Director/Producer
Bonita Engel, Interface Designer

SHOCKWAVE ACTIVITIES:
Mike Enright

JAVASCRIPT ACTIVITIES:
Ronald DeSena: If Rocks Could Talk, Mt. St. Helen's Challenge

Illustrations:
Daryll Collins: pp. 14-15;
Laura Coyle: pp. 3, 5, 9;
Carlyn Iverson: pp. 2, 12-13;
Jim Paillot: pp. 3, 7, 8, 10-11;
©1999 Wayne Vincent: cover.

Photography:
Denis Finnin: pp. 2, 4, 7, 9;
Photo Researcher: cover, p. 6;
pp. 3 (Earth photo) and 5 (Mars photo) courtesy of NASA, pp. 6 (San Francisco Earthquake) and 9 (Mount St. Helens) courtesy of USGS